The bird song system has many parallels to human speech development and maintenance. Like humans, birds depend on hearing their own vocalizations in order to produce song. The main goal of this application is to test whether birds can adapt their vocalizations when auditory feedback is altered and to characterize the neural basis for these behavioral changes. This will be tested by recording the bird's song and playing loud burst of white noise whenever the bird sings a particular pattern of sounds. The playback of white noise targeted at a particular segment of song induces an auditory error signal. In order to reduce this error signal, the bird can either stop singing the targeted sound or change the spectral structure of that sound to avoid detection. The behavioral changes observed will be followed up through electrophysiological investigation of the song system nuclei known to be involved with sensory evaluation and motor production. [unreadable] [unreadable]